Pump system

ABSTRACT

A prosthetic system includes first and second parts rotatable relative to one another about a joint. The first and second parts are adapted to form at least part of a weight bearing connection between a prosthetic foot and a socket. A pump system includes a pump mechanism operatively connected to the first and second parts. Rotation of the first part and/or the second part about the joint moves the pump mechanism between an original configuration in which the volume of a fluid chamber defined by the pump mechanism is zero or near-zero, and an expanded configuration in which the volume of the fluid chamber is increased.

TECHNICAL FIELD

The disclosure relates to the field of prosthetic devices, and moreparticularly to a prosthetic device, system and pump mechanism forincreasing vacuum in a vacuum assisted suspension system.

BACKGROUND

An ongoing challenge in the development of prosthetic devices is theattachment of the prosthetic device to the residual limb of a user. Forprosthetic legs, it is often difficult to securely attach the prostheticleg to the residual leg without exerting too much or uneven pressure onthe residual limb. On the one hand, the lack of a secure attachment canadversely affect the user's ability to walk. On the other hand, animproper fit can cause sores, swelling and pain for the user.

One approach for overcoming this challenge has been the application of anegative pressure vacuum in a space between the limb (or a liner donnedon the limb) and a socket or receptacle coupled to the prosthetic limb.Two conventional ways to apply such a vacuum are by a mechanical pump oran electronic pump.

Mechanical pumps are often in-line systems that utilize the movement ofthe user to generate the negative pressure vacuum in the socket. Forexample, the force generated by contacting the ground during a user'swalking motion can be used to generate a vacuum in the socket space tohold the prosthesis to the user's limb. However, in utilizing the motionof the user, known pumps rely on complete compression of the pump toexpel air from the pump before the pump can be decompressed to generatethe vacuum. Because the impact and displacement of the pump is notconsistent and varies between users, the vacuum and thus attachmentbetween the residual limb and the socket can be unpredictable and/orinadequate, causing the user discomfort, grief and even injury. Many ofsuch pumps are also bulky and significantly contribute to the weight ofthe prosthetic limb, imposing a significant weight burden on the userwhen walking.

There is a need for a prosthetic device, system, and pump mechanism thatprovides freedom of vacuum suspension for a prosthetic system. There isalso a call for a prosthetic device that provides a secure vacuumwithout losing suction and confidence to the user over a period of time.It is also desirable for prosthetic devices to draw a vacuum while beinglightweight and streamlined.

SUMMARY

Embodiments of the prosthetic system provide vacuum assisted suspensionby generating negative pressure inside a prosthetic socket worn over aresidual limb, and reducing sliding movement between the liner and thesocket. The prosthetic system of the present disclosure advantageouslycan produce a vacuum effect in a prosthetic socket utilizing a pivoting,swinging, or rotating mechanism at a joint rather than relying primarilyon a force or pressure applied to the prosthetic system by the user.

According to an embodiment, the prosthetic system includes first andsecond parts rotatable relative to one another about a joint. The firstand second parts form at least part of a weight bearing connectionbetween a prosthetic foot and a socket. A pump system includes a pumpmechanism operatively connected to the first and second parts.

Relative rotation between the first and second parts about the jointmoves the pump mechanism between an original configuration in which thevolume of a fluid chamber defined by the pump mechanism is zero ornear-zero, and an expanded configuration in which the volume of thefluid chamber is increased. For instance, during weight bearing or whena load is applied to the prosthetic system, a support member of the pumpsystem flexes or bends, which, in turn, causes a movable member of thepump system to pivot or rotate about the joint and toward the secondpart.

When the movable member rotates about the joint toward the second part,the movable member rotates away from the support member, which, in turn,moves the pump mechanism toward the expanded configuration, pullingfluid into the pump mechanism. After weight bearing or when the load isremoved, stored energy in the support member forces the first and secondparts to rotate away from one another. This moves the movable member andthe pump mechanism back toward the original configuration, expellingfluid out of the pump mechanism.

The pump system can thus generate a vacuum in a socket using a pivotingor rotating movement between the first and second parts. Further, it cando so without undesirably affecting the functionality of a prostheticknee or foot associated with the prosthetic system or significantlyincreasing the bulk of the system. According to a variation, the pumpsystem can be located at or near the socket such that there is no needto move fluid drawn into the pump mechanism from the socket all the waydown the prosthetic foot. This advantageously reduces the time requiredto produce an elevated vacuum in the socket. Further, it eliminates orreduces the need of a long tube extending between the prosthetic footand the socket, reducing the likelihood of leaks and volume to generatevacuum.

According to a variation, the pump mechanism can be incorporated into aprosthetic knee. For instance, the first part can comprise a rotatablepart of the prosthetic knee.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the presentdisclosure will become better understood regarding the followingdescription, appended claims, and accompanying drawings.

FIG. 1A shows a side view of a prosthetic system according to anembodiment.

FIG. 1B shows another side view of the prosthetic system in FIG. 1A.

FIG. 2 shows a side view of a prosthetic system according to anotherembodiment.

FIG. 3 shows a side view of a prosthetic system according to anotherembodiment.

FIG. 4 shows a side view of a prosthetic system according to anotherembodiment.

FIG. 5 shows a side view of a prosthetic system according to anotherembodiment.

FIG. 6 shows a top view of a prosthetic system according to anotherembodiment.

FIG. 7 shows a side view of the prosthetic system in FIG. 6.

FIG. 8 shows another side view of the prosthetic system in FIG. 6.

FIG. 9 shows a side view of a prosthetic system including the pumpsystem in FIG. 6 according to an embodiment.

FIG. 10 shows a perspective view of a prosthetic system including thepump system in FIG. 6 according to another embodiment.

FIG. 11 shows a perspective view of a pump system according to anotherembodiment.

FIG. 12 shows a side view of a prosthetic system including the pumpsystem in FIG. 11 according to an embodiment.

FIG. 13 shows another side view of the prosthetic system in FIG. 12.

FIG. 14 shows a prosthetic system according to another embodiment.

FIG. 15 shows a cross section view of the prosthetic system in FIG. 14

DETAILED DESCRIPTION OF THE DISCLOSURE

It will be understood that, unless a term is expressly defined in thisdisclosure to possess a described meaning, there is no intent to limitthe meaning of such term, either expressly or indirectly, beyond itsplain or ordinary meaning.

Any element in a claim that does not explicitly state “means for”performing a specified function, or “step for” performing a specificfunction, is not to be interpreted as a “means” or “step” clause asspecified in 35 U.S.C. § 112, paragraph 6.

The embodiments of a prosthetic system will be described which form partof a vacuum system. A vacuum pump system having a fluid connection witha socket assists in creating a vacuum between a residual limb and thesocket by pumping fluid out of the socket. The fluid can be pumped outof the socket manually or in swing and/or stance. For instance, pivotalmovement about a joint between a socket and a pylon of the prostheticsystem can cause a pump mechanism of the present disclosure to increasethe volume of a fluid chamber in the pump mechanism. The increase involume of the pump mechanism draws in fluid from the vacuum spacebetween the residual limb and the socket of a prosthetic system. In thismanner, the pump mechanism decreases the air pressure within the vacuumspace causing a vacuum effect.

The volume of the fluid chamber in the pump mechanism can alsoautomatically decrease. The connection between the vacuum space and thepump mechanism may have a one-way valve assembly, so all of the airwithin the volume of the pump mechanism is expelled out of an outlet toanother space or to atmosphere. The outlet can be provided with aone-way valve assembly so the vacuum space is the only source of air.

The prosthetic system of the present disclosure advantageously canproduce a vacuum effect in a prosthetic socket utilizing a pivoting,swinging, or rotating mechanism at a joint rather than relying primarilyon a force or pressure applied to the prosthetic system by the user. Theprosthetic system of the present disclosure also produces a vacuumeffect that is advantageous over prior art devices that requirecompression of the pump to expel air before the pump can be decompressedto draw in air. The present disclosure achieves smaller fluctuations inair pressure than the prior art systems, so the difference between thegreatest pressure and lowest pressure in the vacuum space of the socketis less.

The pump mechanism embodiments may easily retrofit on existingprosthetic devices and can do so without undesirably affecting theirfunction. They are also lightweight and low-profile, advantageouslycontributing little to no bulk to a prosthetic foot. Optionally, thepump mechanism embodiments can be located at or near the socket suchthat there is no need to move fluid drawn into the pump mechanism fromthe socket down to the prosthetic foot. This advantageously reduces thetime required to produce an elevated vacuum in the socket. Further, iteliminates or reduces the need of a long tube extending between theprosthetic foot and the socket, reducing the likelihood of leaks andvolume to generate vacuum.

The efficiency of the pump mechanism is determined at least in part byhow effectively the volume of the fluid chamber is reduced. Since thepump mechanism begins at and returns to the original state of zero ornear-zero volume, the volume of the fluid chamber is determined by thepivoting force applied to the pump, not by a full compression andrecompression cycle as in the prior art. In addition, all fluid drawninto the pump mechanism is expelled afterwards, fully utilizing thevolume of the fluid chamber.

The vacuum suspension system also reduces volume fluctuations of theresidual limb and allows for increased proprioception and reducedpistoning since there is a better attachment between the socket and theresidual limb. It may also be beneficial to produce hypobaric pressurebelow a certain level in the socket. This may be achieved using asealing membrane or seal component between the residual limb and thesocket, instead of the conventional sealing method of using a sleeve toform an airtight connection between the residual limb and the proximalend of the socket. The sealing membrane may be on a prosthetic liner asdescribed in U.S. Pat. Nos. 8,034,120, 8,894,719, and 9,056,022, allincorporated by reference and belonging to the assignee of thisdisclosure.

The benefit of using a liner having a seal or seal component reduces thevolume of air to be drawn out of the socket and therefore, a bettersuspension may be achieved in a shorter time period. Using a siliconeliner with integrated seal also provides the added benefit that thehypobaric region is not directly applied to the skin.

The vacuum pump mechanisms in the embodiments of the prosthetic systemdescribed are generally described as a pump system or mechanism and mayinclude any suitable type of pump mechanism. For instance, the pumpmechanism may be a pump as described in U.S. Pat. Nos. 9,072,617,9,044,348, 9,486,335, and 9,615,946 and U.S. patent application Ser.Nos. 14/747,788 and 15/457,266, all incorporated by reference andbelonging to the assignee of this disclosure. A piston-type pump may beused in the embodiments in place of a membrane-type pump. A bladder-typepump may also be used in the embodiments in place of a membrane-typepump, and a skilled person would understand that the pump mechanismsdescribed may also be used with a bladder-type pump and vice versa.

A bladder-type pump has an interior fluid chamber surrounded by anairtight material. When the interior chamber is expanded, the opposingwalls are moved away from each other by extending at least one side wallof the pump. The side walls of the bladder-type pump may have anaccordion-like shape or be formed of a polymeric material which allowfor the increase in distance between the opposing walls.

A membrane-type pump has at least one wall of flexible material and asecond opposing wall which may be rigid or flexible. The edges of thetwo walls are attached to each other such that when a force applies tothe pump to expand the interior fluid chamber, the force deforms atleast the flexible wall, and the flexible wall arcs outward to form aninterior fluid chamber. To allow for deformation, the flexible wall maybe made of a polymeric material including elastomeric material such asrubber or plastic.

The bladder-type pump and membrane-type pump are arranged so that theinitial volume of the interior fluid chamber is zero or near-zero. Thepumps described and shown have a cylindrical shape. A skilled personwould understand that the pumps may have a variety of shapes, forexample, a diamond, rectangular, or triangular shape.

The specific embodiments of the prosthetic device will now be describedregarding the figures.

FIGS. 1A and 1B show a prosthetic system 1 including a pump system 3. Asseen in FIG. 1A, the pump system 3 comprises a prosthetic connectorhaving a pump mechanism 5, an upper section 7, and a lower section 9.The prosthetic connector is arranged to form at least part of a weightbearing connection 2 between a prosthetic foot 4 and a socket 6 asshown. A tube 20 and valve 22 can connect the pump mechanism 5 to thesocket 6. The lower section 9 is spaced apart from the upper section 7by a clearance 36. When the upper and lower sections 7, 9 are in thepredetermined configuration, as shown in FIG. 1A, the upper and lowersections 7, 9 are aligned along a same axis A extending along the weightbearing connection 2 from the prosthetic foot 4 to the socket 6.

At least one of the upper and lower sections 7, 9 is arranged to rotateor move relative to the other. In an embodiment, the upper section 7includes an attachment adaptor 11 and the lower section 9 includes anattachment adaptor 13. The adaptors 11, 13 are shown as female adaptorsbut can be male adaptors or any other suitable attachment adaptors.

A support member 15 connects the upper section 7 and the lower section9. The support member 15 has load-carrying configuration and defines ajoint 16 about which at least one of the upper and lower sections 7, 9pivots relative to the other. When no load is placed on the prostheticsystem 1, the support member 15 maintains its shape and supports theupper section 7 and the lower section 9 a distance from one another.When a load is placed on the prosthetic system 1, the support member 15flexes or bends, which, in turn, pivots the upper and lower sections 7,9 relative to one another about the joint 16. The joint 16 can belocated anywhere along the length of the support member 15. The supportmember 15 can be made of polymer material, carbon fiber, metal,combinations thereof, or any other suitable material.

The pump mechanism 5 is positioned in a receiving space 19 definedbetween the support member 15 and the movable member 17. The pumpmechanism 5 includes a housing 21 attached to the support member 15 anda membrane 23 operatively connected to a movable member 17. The pumpmechanism 5 may include at least one valve assembly 18 arranged tocontrol movement of fluid into and from the pump mechanism 5.

The pump mechanism 5 relies upon deformation of the membrane 23 to movebetween an original configuration (shown in FIG. 1A) in which the volumeof a fluid chamber 29 defined between the membrane 23 and the housing 21is zero or near-zero, and an expanded configuration (shown in FIG. 1B)in which the volume of the fluid chamber 29 is increased.

When a force F is exerted on the membrane 23 in a direction away fromthe housing 21, the pump mechanism 5 moves toward the expandedconfiguration (shown in FIG. 1B) as the force pulls the center portionof the membrane 23 away from the housing 21, causing deformation of themembrane 23 and an increase in volume of the fluid chamber 29. Thisincrease in volume of the fluid chamber 29 can draw fluid into the fluidchamber 29 from the socket 6 through at least one valve assembly 18. Thehousing 21 may be formed of metal such as stainless steel, carbon fiber,or plastic or any other material which would provide sufficient strengthto resist deformation when pulled away from the membrane 23.

Once the force F is removed from the membrane 23, the pump mechanism 5returns toward its original configuration (shown in FIG. 1A) as themembrane 23 returns toward the housing 21 and fluid within the fluidchamber 29 is expelled out of the at least one valve assembly. Themembrane 23 can be elastomeric and can use at least in part its materialproperties to naturally or elastically return to its original positionon the housing 21.

The membrane 23 may have any desired shape but is shown having agenerally elliptical or circular shape. The membrane 23 can be attachedat or near its center point to the movable member 17 via a connector 27while the outer radial edge portion of the membrane 23 is attached tothe housing 21. When the membrane 23 is pulled away from the housing 21,a pocket forms in the middle area of the membrane 23 due to thedeformation of the membrane 23. The formation of the pocket increasesthe volume of the fluid chamber 29. The pump mechanism 5 thus uses acompliant membrane to create suction. The connecter 27 can be an insertformed of metal, plastic, or any other suitable material. In otherembodiments, the connector 27 may be formed of a material that is partof the membrane 23.

The movable member 17 has a rigid configuration and is connected to thesupport member 15. The movable member 17 can include a base part 17A andan elongated part 17B. The base part 17A can be attached to a proximalportion of the support member 15 and extends a distance outwardlytherefrom. The elongated part 17B extends generally downward from thebase part 17A and is connected to the membrane 23 via the connector 27.

The movable member 17 can define an opening or slot for receiving theconnector 27. To attach the movable member 17 to the membrane 23, ashaft portion of the connector 27 can be received in the opening or slotsuch that the elongated part 17B of the movable member 17 is connectedto the connector 27. The connector 27 can be attached to the movablemember 17 via a pin, nut, flange, removable head portion, or otherfastener. Through the structure of the connector 27 and the movablemember 17, the pump mechanism 5 has the benefit of being easily andquickly removed and/or replaced from prosthetic system 1.

During weight bearing or when a load is applied to the prosthetic system1, the support member 15 flexes or bends, which, in turn, causes theupper section 7 and the base part 17A of the movable member 17 to pivotor rotate about the joint 16 and toward the lower section 9 as seen inFIG. 1A.

When the base part 17A rotates about the joint 16 toward the lowersection 9, the elongated part 17B of the movable member 17 rotates awayfrom the support member 15, which, in turn, causes the connector 27 topull the membrane 23 away from the housing 21, increasing the volume ofthe fluid chamber 29. This increase in volume of the fluid chamber 29creates a vacuum in the pump mechanism 5, pulling fluid into the pumpmechanism 5. Pivoting movement between the upper and lower sections 7, 9thus automatically creates a vacuum in the pump mechanism 5.

After weight bearing or when the load is removed, stored energy in thesupport member 15 forces the upper and lower sections 9, 11 to rotateaway from one another. This moves the elongated part 17B of the movablemember 17 back toward the housing 21, moving the membrane 23 toward thehousing 21 and expelling fluid within the fluid chamber 29 out of thepump mechanism 5. As such, the support member 15 can both move the pumpmechanism 5 toward the expanded configuration when loaded, and bias thepump mechanism 5 from the expanded configuration toward the originalconfiguration when unloaded.

The pump system 3 can thus generate a vacuum in a socket using apivoting or swinging movement between the upper and lower sections 9, 11without undesirably affecting the functionality of a prosthetic footassociated with the system or significantly increasing the bulk of theprosthetic system 1.

The pump system 3 is shown being located closer to the foot 4 than thesocket 6 but it will be appreciated that the pump system 3 can belocated at any suitable position within the system 1. For instance, thepump system 3 can be located nearer to the socket 6 such that there isno need to move fluid drawn into the pump mechanism from the socket 6down to the prosthetic foot 4. This advantageously reduces the timerequired to produce an elevated vacuum in the socket. Further, iteliminates or reduces the need of a long tube extending between theprosthetic foot and the socket, reducing the likelihood of leaks andvolume to generate vacuum.

FIG. 2 illustrates a prosthetic system 31 including a pump system 33according to another embodiment. The system 31 includes a prostheticknee 35 and a pylon 37 connected to the prosthetic knee 35. Theprosthetic knee 35 can be any suitable prosthetic knee and is arrangedto form at least part of a weight bearing connection between aprosthetic foot and a socket.

In order to better understand the operation of the system 31, a basicdiscussion of the gait cycle is provided. A gait cycle defines themovement of the leg between successive heel contacts of the same foot.The gait cycle has two phases: stance and swing. The stance phase hasthree time periods: heel-strike, mid-stance and toe-off. Duringmid-stance, the knee joint will be at full extension. Maximum flexion ofthe knee joint, while walking, will occur at the end of the toe-offphase. Immediately following the end of the toe-off phase begins theswing phase.

While the stance phase has three time periods, the swing phase has twotime periods: acceleration and deceleration. The acceleration phasebegins immediately following the maximum flexion during the toe-offphase. During the acceleration phase, the lower portion of the leg,comprising the shin and foot, swings back towards full extension. In anatural knee joint, a deceleration phase follows the acceleration phase,during which the lower portion of the leg continues to swing towardsfull extension.

The knee 35 includes a proximal part 39, a distal part 41, and a link 43connecting the proximal part 39 and the distal part 41. According to avariation, the link 43 can comprise a load-dependent brake system 43arranged to selectively prevent rotation of the proximal part 39relative to the distal part 41 when the knee 35 is loaded by a user instance. When the load on the knee 35 is removed or reduced, theload-dependent brake system can be released and the knee 35 can swing orthe proximal part 39 can rotate relative to the distal part 41 about ajoint 42 defined by the link 43. The pylon 27 can be attached to anattachment adaptor positioned at the top of the proximal part 39 and adistal tube clamp attachment 44.

The pump system 33 includes a pump mechanism 45 and a movable member 47.The pump mechanism 45 includes a housing 49, a membrane 51, and at leastone valve assembly 53 arranged to control movement of fluid into andfrom the pump mechanism 45. The housing 49 comprises a base plateattached to the anterior portion of the distal part 41.

The pump mechanism 45 relies upon deformation of the membrane 51 to movebetween an original configuration in which the volume of a fluid chamber55 defined between the membrane 51 and the housing 49 is zero ornear-zero, and an expanded configuration (shown in FIG. 2) in which thevolume of the fluid chamber 55 is increased. The membrane 51 may haveany desired shape.

The membrane 49 can be attached at or near its center point to themovable member 47 via a connector 57 while the outer radial edge portionof the membrane 51 can be attached to the housing 49. When the membrane51 is pulled away from the housing 49, a pocket forms in the middle areaof the membrane 51 due to the deformation of the membrane 51. Theformation of the pocket increases the volume of the fluid chamber 55,creating suction. The connector 57 can be made of any suitable material.In an embodiment, the connector 57 can define a through channel in fluidcommunication with the fluid chamber 55 and the at least one valveassembly 53.

The movable member 47 has a rigid configuration and is located on theanterior portion of the knee 35 and spans the proximal part 39 and thedistal part 41. The movable member 47 can define an opening or slot forreceiving the connector 57. Through the structure of the connector 57and the movable member 47, the pump system 33 has the benefit of beingeasily and quickly removed and/or replaced from the system 31. Themovable member 47 includes a distal end portion 59 arranged to engagethe distal part 41 of the knee 35 and a proximal end portion 61 arrangedto engage the distal part 39 of the knee 35. The distal end portion 59of the movable member 47 can be pivotally connected to the knee 35 at ornear a distal region thereof.

At extension of the knee 35, the proximal end portion 61 engages theproximal part 39 as the proximal part 39 rotates in a counterclockwisedirection about the joint 42. This pushes the movable member 47 awayfrom the housing 49 and causes the connector 57 to pull the membrane 51away from the housing 49, increasing the volume of the fluid chamber 55.This increase in volume of the fluid chamber 55 creates a vacuum in thepump mechanism 45, pulling fluid into the pump mechanism 45 through atube 63 attached to the socket.

During flexion of the knee 35, the proximal end portion 61 disengagesthe proximal part 39 as the proximal part 39 rotate about the joint 42to decrease the angle therebetween, which, in turn, allows the pumpmechanism 45 to return toward its original configuration. As themembrane 51 returns toward the housing 49, fluid within the fluidchamber 55 is expelled out of the at least one valve assembly 53. Asnoted above, the membrane 51 can be elastomeric and can use at least inpart its material properties to naturally or elastically return to itsoriginal position on the housing 49. Optionally, the pump mechanism 45can include a closure-assist mechanism arranged to bias or move the pumpmechanism 45 toward its original configuration and/or maintain ittherein.

The pump system 33 can thus generate a vacuum using the swinging orpivoting movement of the knee 35 without undesirably affecting thefunctionality of the knee or significantly increasing the bulk of theprosthetic system 31. In addition, the pump mechanism 45 can be locatednearer to the socket such that there is no need to move fluid drawn intothe pump mechanism from the socket down to a prosthetic foot. Thisadvantageously reduces the time required to produce an elevated vacuumin the socket. Further, it eliminates or reduces the need of a longertube extending between the prosthetic foot and the socket, reducing thelikelihood of leaks and volume to generate vacuum. While the pump systemis shown positioned on the anterior of the knee, it will be appreciatedthat the pump system can be positioned at any suitable position on aknee.

FIG. 3 illustrates yet another embodiment of a pump system located on aposterior aspect of a prosthetic knee. As shown, a prosthetic system 63including a pump system 65 is positioned on a posterior aspect P of aprosthetic knee 67. The system 63 includes a socket assembly 69 arrangedto embrace a residual limb and the prosthetic knee 67 connected to thesocket assembly 69. The socket assembly 69 can be attached to anattachment adaptor 71 positioned at the top the knee 67. The knee 67defines a joint 84 and a first part 83 arranged to rotate about thejoint 84. The knee 67 is arranged to form at least part of a weightbearing connection between a prosthetic foot and the socket assembly 69.

The pump system 65 includes a pump mechanism 73, a movable member 75,and a protrusion 81 on the first part 83 of the knee 67. The pumpmechanism 73 includes a housing 77, a membrane 79, and at least onevalve assembly arranged to control movement of fluid into and/or fromthe pump mechanism 73. The housing 77 is attached to the posterioraspect P of the attachment adaptor 71.

The pump mechanism 73 relies upon deformation of the membrane 79 to movebetween an original configuration in which the volume of a fluid chamber85 defined between the membrane 79 and the housing 77 is zero ornear-zero, and an expanded configuration (shown in FIG. 3) in which thevolume of the fluid chamber 85 is increased. The membrane 79 may haveany desired shape.

The membrane 79 can be attached at or near its center point to themovable member 75 while the outer radial edge portion of the membrane 79can be attached to the housing 77. The membrane 79 can be attached tothe movable member 75 via a connecter 87. The connector 87 can be madeof any suitable material. In an embodiment, the connector 87 can definea through channel in fluid communication with the fluid chamber 85 andthe at least one valve assembly.

The movable member 75 has a rigid configuration and includes a proximalend portion 89 attached to the housing 77 at a first location point 91.In the illustrated embodiment, the movable member 75 can be pivotallyattached to the housing 77 at the first location point 91. In otherembodiments, the movable member 75 can be arranged to flex or bend at ornear the first location point 91. The movable member 75 can be integralto the housing 77.

The movable member 75 includes a distal end portion 93 arranged toselectively engage the protrusion 81 on the first part 83 of the knee67. The protrusion 81 can have any suitable shape but is shown having arounded or curved outer surface. The protrusion 81 can be attached tothe first part 83 of the knee 67. The protrusion 81 can be integral tothe first part 83. The protrusion is arranged to selectively lift themovable member 75 away from the housing 77 by engaging the distal endportion 93 of the movable member 75.

At extension of the knee 67, the protrusion 81 on the first part 83 ofthe knee 76 engages the distal end portion 93 of the movable member 75as the first part 83 straightens relative to the socket assembly 69,which, in turn, lifts or rotates the movable member 75 away from thehousing 77. This causes the connector 87 to pull the membrane 79 awayfrom the housing 77, increasing the volume of the fluid chamber 85. Thisincrease in volume of the fluid chamber 85 creates a vacuum in the pumpmechanism 73.

During flexion of the knee 67, the protrusion 81 disengages the distalend portion 93 of the movable member 75, which, in turn, allows the pumpmechanism 73 to return toward its original configuration. As themembrane 79 returns toward the housing 77, fluid within the fluidchamber 85 is expelled out of the pump mechanism 73. According to avariation, the movable member 75 can be arranged to bias the pumpmechanism 73 toward its original configuration.

Similar to the previous embodiment, the pump system 65 can thus generatea vacuum using the swinging or pivoting movement of the knee 67 withoutundesirably affecting the functionality of the knee or significantlyincreasing the bulk of the prosthetic system 63. In addition, the pumpmechanism 73 can be located nearer to the socket assembly 69 such thatthere is no need to move fluid drawn into the pump mechanism 73 from thesocket system 69 down to a prosthetic foot.

FIG. 4 illustrates a prosthetic system 95 including a pump system 97according to another embodiment. The prosthetic system 95 is similar instructure and function to the prosthetic system 63 except that the pumpsystem is located on a side of the prosthetic knee. For instance, thepump system 97 includes a pump mechanism 99, a movable member 101, and aprotrusion or ramp member 103 on the first part 83 of the knee 67.

The pump mechanism 99 includes a housing 102, a membrane 105, and atleast one valve assembly 110 arranged to control movement of fluid intoand/or from the pump mechanism 99. The housing 102 is attached to asecond part 107 of the knee 67 that is rotatable relative to the firstpart 83.

Similar to the previously described embodiments, the pump mechanism 99relies upon deformation of the membrane 105 to move between an originalconfiguration in which the volume of a fluid chamber defined between themembrane 105 and the housing 103 is zero or near-zero, and an expandedconfiguration in which the volume of the fluid chamber is increased.

The membrane 105 can be attached at or near its center point to themovable member 101 while the outer radial edge portion of the membrane105 can be attached to the housing 103. The membrane 105 can be attachedto the movable member 101 via a connector 111.

The movable member 101 has a rigid or semi-rigid configuration andincludes a distal end portion 115 connected to the housing 103. Themovable member 101 has an elongate configuration that extends from thedistal end portion 115 toward a proximal end portion 109. The movablemember 101 can be integral to the housing 103. The movable member 101can be cantilevered from the housing 101 with the proximal end portion109 spaced a distance from a side surface of the first part 83.

The proximal end portion 109 is arranged to selectively engage and slidealong the protrusion 103 on the first part 83 of the knee 67. Theprotrusion 103 can have a ramp shape including an inclined contactsurface 113 arranged to lift the proximal end portion 109 of the movablemember 101 away from the housing 103 as it slides up the protrusion 103.

Upon flexion of the knee 67, the proximal end portion 109 engages andslides up the contact surface 113 of the protrusion 103, which, in turn,lifts or rotates the movable member 101 away from the housing 103. Thiscauses the connector 111 to pull the membrane 99 away from the housing103, increasing the volume of the fluid chamber.

At extension of the knee 67, the proximal end portion 109 and theprotrusion 103 disengage, which, in turn, allows the pump mechanism 99to return toward its original configuration. As the membrane 105 returnstoward the housing 105, fluid within the fluid chamber is expelled outof the at least one valve assembly 107. Optionally, the movable member101 can be arranged to bias the pump mechanism 99 toward its originalconfiguration. The pump system 97 can thus advantageously generate avacuum using flexion of the knee 67.

It will be appreciated that locating the pump mechanism 99 where it canbe easily reached by a user's hand allows the pump mechanism 99 to bemanually activated by the user rather than automatically by theprosthetic knee. For instance, by positioning the pump mechanism 99 onthe side of the knee 67 and manipulating the movable member 101, a usercan generate and maintain a vacuum pressure in a socket. In otherembodiments, embodiments of the pump mechanism can be located on asocket itself and manually operated by a user.

FIG. 5 illustrates a prosthetic system 117 including a pump system 119according to an embodiment. The pump system 119 comprises a prostheticconnector 120 defining a cavity 129 and including an upper section 131and a lower section 133. As seen, the upper section 131 can include anattachment adaptor 135 and the lower section 133 can include anattachment adaptor 137. The adaptors 135, 137 are shown as male adaptorsbut can be female adaptors or any other type of attachment adaptors. Itwill be appreciated that the prosthetic connector 120 is arranged toform at least part of a weight bearing connection between a prostheticfoot and a socket.

A pump mechanism 121 is located in the cavity 129. The pump mechanism121 includes a plate member 139, a membrane 125, and a pendulum typemechanism 127. An outer radial edge portion of the membrane 125 can beattached to the plate member 139. A center portion of the membrane 125can be attached to the pendulum type mechanism 127. For instance, thependulum type mechanism 127 can comprise a pivoting weighted member 145suspended from a pivot at or near the center portion of the membrane 125via an elongated member 148 so that it can swing freely.

A first fluid passageway 141 extends through the upper section 131 andthe plate member 139 and a second fluid passageway 143 extends throughthe membrane 125 and the pendulum type mechanism 127. The pump mechanism121 can include a first valve assembly 147 positioned in the firstpassageway 141 that is arranged to control movement of fluid into thepump mechanism 121. A second valve assembly 149 can be positioned in thesecond fluid passageway 143 to control movement of the fluid out of thepump mechanism 121.

The pump mechanism 121 relies upon deformation of the membrane 125 tomove between an original configuration (shown in FIG. 5) in which thevolume of a fluid chamber 151 defined between the membrane 125 and theplate member 139 is zero or near-zero, and an expanded configuration inwhich the volume of the fluid chamber 151 is increased.

In an embodiment, swinging or pivoting movement of the weighted member145 from a neutral position (shown in FIG. 5) during gait can move thepump mechanism between the original and expanded configurations. Forinstance, during flexion, the weighted member 145 can swing back and/orforth from the neutral position and the momentum of the weighted member145 can exert a dynamic tensile force on the membrane 125 to move thepump mechanism between the original and expanded configuration. In otherembodiments, the weighted member 145 can swing in unrestricted 360directions relative to the neutral position. This pulls the membrane 125away from the plate member 139, increasing the volume of the fluidchamber 151. The increase in volume of the fluid chamber 151 creates avacuum in the pump mechanism 121, pulling fluid into the pump mechanism121 through the first valve assembly 147.

At extension, the weighted member 145 can swing back toward the neutralposition, which, in turn, allows the pump mechanism 121 to return towardits original configuration. As the membrane 125 returns toward the platemember 139, fluid within the fluid chamber 151 is expelled out of thepump mechanism 121 via the second valve assembly 149.

According to a variation, the pump system 119 can include aclosure-assist mechanism arranged to bias the pump mechanism 121 towardthe original configuration. For instance, a first magnet 153 can belocated on a bottom of the cavity 127 and a corresponding second magnetor ferromagnetic member 155 can be located at the base of the weightedmember 145. Magnetic forces between the first and second magnets 153,155 can function to bring the weighted member 145 back toward theneutral position. While the closure-assist mechanism is describedcomprising a plurality of magnets, in other embodiments, theclosure-assist mechanism can comprise a resilient spring member.

The pump system 119 can thus advantageously draw a vacuum through randomor gait motion of the prosthetic system 117, making the pump system 117more efficient and versatile. Further, the pump system 117 can be placedanywhere near or around the socket or a prosthetic knee.

FIGS. 6-8 show a pump system 157 according to yet another embodiment.The pump system 157 includes a suction cup type pump mechanism.Embodiments of the suction cup type pump mechanism can be adapted to avariety of prosthetic components and to prosthetic feet that areparticularly difficult to operate with conventional pump mechanisms,providing versatility.

The pump system 157 comprises a pump mechanism 159 having a suction cuptype configuration. The pump mechanism 159 includes an elastomermembrane 161 arranged to be positioned on a sealing surface 163. Thesealing surface 163 can comprise an outer surface of a socket, a footplate, or any other suitable sealing surface. As such, the membrane 161of the pump mechanism 159 can advantageously be sealed on a variety ofprosthetic components and prosthetic feet provided that such componentsand feet can provide the sealing surface 163.

The membrane 161 is arranged to form a seal with the sealing surface163. In other words, when there is less pressure in a fluid chamber 167defined between a bottom of the membrane 161 and the sealing surface 163than on the outer side of the membrane 161, the pressure differentialpushes the membrane 161 down against the sealing surface 163, forcingfluid out and stopping fluid from entering under the edges of themembrane 161 into the fluid chamber 167.

Similar to the other embodiments, the pump mechanism 159 relies upondeformation of the membrane 161 to move between an originalconfiguration in which the volume of the fluid chamber 167 is zero ornear-zero, and an expanded configuration in which the volume of thefluid chamber is increased. The membrane 161 can have any suitableshape. For instance, the bottom of the membrane 161 can define a concavecurvature.

The membrane 161 defines a passageway 165 in fluid communication withthe fluid chamber 167. The passageway 165 can include a fitting 166arranged to be attached to a tube. According to a variation, a valveassembly can be integrated with the tube or the passageway 165 that isarranged to only allow fluid to enter the fluid chamber 167 via thepassageway 165. The valve assembly can comprise a duck-bill valve.

With the membrane 161 sealed on the sealing surface 163, the applicationof back and forth movement to the membrane 161 can move the pumpmechanism 159 between the expanded and original configurations. Forinstance, when no force is exerted on a center portion of the membrane161 to expand the fluid chamber 167, the volume of the fluid chamber 167is zero or near-zero as seen in FIG. 7. When a force F is exerted on thecenter portion of the membrane 161 to expand the fluid chamber 167, thevolume of the fluid chamber 167 is increased, moving the pump mechanism159 toward the expanded configuration as seen in FIG. 8.

The pump system 157 can thus advantageously create a vacuum using simpleand/or random motion to function. The pump system 157 advantageouslyalso does not require a separate mechanism or structure to operate themembrane 161 to create a vacuum in a socket.

According to a variation, as the pump mechanism 159 moves from theexpanded configuration toward the original configuration, pressurewithin the fluid chamber 167 increases until the seal between themembrane 161 and the sealing surface 163 is broken, allowing fluid inthe fluid chamber 167 to escape or be expelled out under the sides ofthe membrane 161. The pump mechanism 159 thus does not require an outletvalve assembly, reducing the overall weight and profile of the pumpsystem 157.

FIG. 9 illustrates a prosthetic system 169 including the pump system 157according to an embodiment. The prosthetic system 169 includes a socketassembly 171 arranged to receive a residual limb and a prosthetic knee173 connected to the socket assembly 171. The socket assembly 171 can beattached to an attachment adaptor 175 positioned at the top of the knee173. The knee 173 includes a proximal part 177 and a distal part 179attached to the proximal part 177. The proximal part 177 and the socketsystem 171 are arranged to rotate relative to one another about a joint181 defined by the knee 173. It will be appreciated that the knee 173 isarranged to form at least part of a weight bearing connection between aprosthetic foot and a socket.

The membrane 161 of the pump mechanism 159 is sealed or placed on asealing surface 183 defined by an outer surface 185 on the posterioraspect P of the socket assembly 171. A tube 187 connects the pumpmechanism 159 to the socket assembly 171 via a valve assembly 188 thatis attached to an aperture defined in the socket assembly 171. The tube187 can be threadedly attached to the threaded fitting 166 of themembrane 161.

A movable member 189 comprising a transfer element operatively connectsthe pump mechanism 159 to the distal part 179 of the knee 173. Thetransfer element 189 can be a cable, a lace, a wire or any othersuitable member and may refer to a relatively long and relatively thinshaped member and may include a friction reducing coating. The transferelement 189 may be made of any type of material which would provide thetransfer element 189 with some rigidity and stiffness including metal,plastic, or fiberglass. The transfer element 189 translates action ofthe knee 173 to the pump mechanism 159.

According to a variation, the prosthetic system 169 can include atensioning control mechanism to adjust the length of the transferelement 189. In an embodiment, the transfer element 189 may be placedwithin a tubular casing. The tubular casing may be made of a variety ofmaterials including plastic or an elastomeric material.

A first end of the transfer element 189 is attached to the pumpmechanism 159. The first end of the transfer element 189 can be attachedto the threaded fitting 166. From the pump mechanism 159, the transferelement 189 passes through an anchor point 193 on the proximal part 177of the knee 173 which directs the transfer element 189 downwardly towardthe distal part 179 of the knee 173. At the distal part 179 of the knee173, a second end of the transfer element 189 is attached to theposterior aspect P of the distal part 179.

When the prosthetic system 169 is in flexion, there is slack in thetransfer element 189 and the pump mechanism 159 is in its originalconfiguration. As the prosthetic system 169 moves from flexion towardextension, the distal part 179 of the knee 173 rotates about the joint181 away from the socket system 171. This causes the transfer element189 to tighten and apply a pulling force on the pump mechanism 159.

The pulling force on the pump mechanism 159 causes the membrane 161 topull away from the sealing surface 183, moving the pump mechanism 159 tothe expanded configuration. More particularly, the transfer element 189pulls the membrane 161 away from the sealing surface 183 on the socketassembly 171, increasing the volume of the fluid chamber defined betweenthe membrane 161 and the sealing surface 183. This increase in volume ofthe fluid chamber creates a vacuum in the pump mechanism 159, pullingfluid into the pump mechanism 159 through the tube 187.

As the prosthetic system 169 moves from extension to flexion, thetransfer element 189 loosens and the pump mechanism 159 can move backtoward its original configuration and decreases the volume of the fluidchamber to zero or near zero. According to a variation, the transferelement 189 has a rigidity and stiffness such that movement fromextension to flexion causes the transfer element 189 to slide inside ofthe tubular casing and exert a pushing force on the membrane 16, pushingthe membrane 161 back toward the sealing surface 183.

During the return of the membrane 161 toward the sealing surface 183,the increased pressure in the fluid chamber can break the seal betweenthe membrane 161 and the sealing surface 183, allowing fluid in thefluid chamber to be expelled out under the membrane 161. Because thepump mechanism 159 returns to its original configuration of zero ornear-zero volume in the fluid chamber at the beginning or end of eachgait cycle, substantially all fluid drawn into the pump mechanism 159 isautomatically expelled.

The prosthetic system 169 can thus advantageously use the swinging orpivoting movement between the socket assembly 171 and the distal part179 of the prosthetic knee 173 to automatically generate a vacuum in thesocket assembly 171. In addition, because the pump mechanism 159 isattached directly to the socket assembly 171, the user can easilyactivate the pump mechanism 159 manually.

FIG. 10 shows yet another embodiment of the pump system 157 implementedwith a prosthetic foot. As seen, a prosthetic system 195 can include aprosthetic foot 197 and the pump system 157 secured directly to the foot197. A tube 198 can fluidly connect the pump system 157 to a prostheticsocket. The membrane 161 of the pump mechanism 159 can be sealed orplaced on a sealing surface 199 defined by a proximal surface of thefoot 197, providing a sleek and low-profile design.

During gait, the random and/or simple movement between the sealingsurface 199 on the foot 197 and the membrane 161 can advantageouslycreate a vacuum in a socket and expel fluid drawn out of the socket toatmosphere while contributing little to no bulk to the foot 197. Thepump system 157 can be secured to the foot 197 so that there is areduced likelihood of the pump system 157 undesirably affecting thefunctionality of the foot 197, providing a more natural gait.

FIGS. 11-13 show another embodiment of a pump system 201 having asuction cup type configuration adaptable to fit a variety of prostheticcomponents. Additionally, the pump system 201 can use swinging movementat a joint to activate the pump system 201 rather than using the user'sweight applied to the prosthetic component.

As seen, the pump system 201 can include a pump mechanism 203 comprisinga base plate 205, a membrane 207, and a top plate 209. The membrane 207defines a bottom arranged to be sealed or placed on a sealing surface211 defined by the base plate 205.

The pump mechanism 203 relies upon deformation of the membrane 207 tomove between an original configuration in which the volume of a fluidchamber 213 (best seen in FIG. 13) defined between the bottom of themembrane 207 and the sealing surface 211 is zero or near-zero, and anexpanded configuration in which the volume of the fluid chamber 213 isincreased. The membrane 207 can have any suitable shape but is shownhaving a shape generally corresponding to the base plate 205.

The membrane 207 defines a passageway 215 in fluid communication withthe fluid chamber 213. The pump mechanism 203 can include a fitting 217in fluid communication with the passageway 215 and arranged to beattached to a tube. Optionally, a valve assembly can be integrated withthe fitting 217 or a tube associated with the fitting 217. The valveassembly can be arranged to only allow fluid to enter the fluid chamber213 via the passageway 215.

According to a variation, as the pump mechanism 203 moves from theexpanded configuration toward the original configuration, pressurewithin the fluid chamber 213 increases until the seal between themembrane 207 and the sealing surface 211 is broken, allowing fluid inthe fluid chamber 213 to escape out under the sides of the membrane 207.

The top plate 209 has an angled configuration including a first part 219connected to center portion of the top of the membrane 207 and a secondpart 221 angled relative to the first part 219 and extending toward afree end. A variable clearance 213 is defined between the bottom of thesecond part 221 and the top of the membrane 207. In other embodiments,the top plate 209 can have a curved configuration, a linearconfiguration, an angled configuration, or combinations thereof.

The top plate 209 is arranged to move the pump mechanism 203 between theoriginal and expanded configurations by rocking back and forth relativeto the base plate 205.

With the first part 219 of the top plate 209 generally parallel to thebase plate 205 and the second part 221 angled upwardly from the firstpart 219, the pump mechanism 203 is in the original configuration (shownin FIG. 11). Rotation of the second part 221 toward the base plate 205decreases the clearance 213 and rotates the first part 219 away from thebase plate 205, which, in turn, pulls a center portion of the membrane207 away from the sealing surface 211. Pulling the center portion of themembrane 207 away from the sealing surface 211 deforms the membrane 207,moving the pump mechanism 205 toward the expanded configuration.

When the second part 221 rotates away from the base plate 205(increasing the clearance 213) and the first part 219 rotates toward thebase plate 205, the pump mechanism 203 returns toward its originalconfiguration (shown in FIG. 11) as the membrane 207 returns toward thesealing surface 211. The membrane 207 can use at least in part itsmaterial properties to naturally or elastically return to its originalposition on the sealing surface 211.

FIGS. 12 and 13 illustrates a prosthetic system 223 including the pumpsystem 201 according to an embodiment. As seen, the pump system 201 isattached to an anterior aspect of a prosthetic knee 225. The knee 225includes a proximal part 227 and a distal part 229 attached to theproximal part 227. The proximal part 227 and the distal part 229 arearranged to relative to one another about a joint 230 defined by theknee 225. It will be appreciated that the knee 225 is arranged to format least part of a weight bearing connection between a prosthetic footand a socket.

A movable member 231 comprising an arm 233 is attached to the proximalpart 227 of the knee 225. The arm 233 has an elongate configuration andextends generally downward from the outer surface of the proximal part227. The arm 233 defines a distal portion 235 arranged to selectivelyengage the second part 221 of the top plate. The arm 233 may be made ofany type of material which would provide the arm 233 with rigidity andstiffness including metal, plastic, carbon fiber, or the like. The arm233 translates swinging or pivoting action of the knee 225 to the pumpmechanism 203.

When the knee 225 is in flexion, the distal portion 235 of the arm 233is separated or spaced a distance from the second part 221 of the topplate 209 and the pump mechanism 203 is in its original configuration asseen in FIG. 12.

As the knee 225 moves from flexion toward extension as seen in FIG. 13,the distal portion 235 of the arm 233 engages and applies directpressure or force on the second part 221 of the top plate 209 of thepump mechanism 205. The applied pressure or force causes the second part221 of the top plate 209 to rotate toward the base plate 205 and thefirst part 219 of the top plate 209 to rotate away from the base plate205, moving the pump mechanism 203 to the expanded configuration. In anembodiment, the first part 219 of the top plate 209 pulls a centerportion of the membrane 207 away from the sealing surface 211,increasing the volume of the fluid chamber 213. This increase in volumeof the fluid chamber 213 creates a vacuum in the pump mechanism 205,pulling fluid into the fluid chamber 213 through the passageway 215.

As the knee 225 moves from extension and flexion, the distal portion 235of the arm 233 disengages from the first part 219 of the top plate 209and the pump mechanism 203 can move back toward its originalconfiguration. During the return of the membrane 207 toward the sealingsurface 211, the increased pressure in the fluid chamber 213 can breakthe seal between the membrane 207 and the sealing surface 211, allowingfluid in the fluid chamber 213 to be expelled out under the membrane207. Because of the pump mechanism 203 returns to its originalconfiguration of zero or near-zero volume in the fluid chamber at thebeginning or end of each gait cycle, substantially all fluid drawn intothe pump mechanism 203 is automatically expelled.

The prosthetic system 223 can thus beneficially use the swinging orpivoting movement of the knee 225 to automatically generate a vacuum ina socket or socket assembly. The pump mechanism 203 is located near thesocket such that there is no need to move fluid drawn into the pumpmechanism 203 from the socket to a prosthetic foot. This beneficiallyreduces the time required to produce an elevated vacuum in the socket.It also eliminates or reduces the need of a long tube extending betweenthe prosthetic foot and the socket, reducing the likelihood of leaks andvolume to generate vacuum.

FIGS. 14 and 15 illustrate yet another embodiment of a prosthetic system237 including a pump system 239. As noted above, embodiments of the pumpsystem can be adapted to fit prosthetic feet that are particularlydifficult to operate with a conventional pump mechanism.

For instance, the prosthetic system 237 can include a prosthetic sportfoot 241 arranged to efficiently store and release energy producedduring running to improve performance. The prosthetic running foot 241has a plate-like member 243 having an overall curved profile. A proximalportion of the plate-like member 243 can have an attachment adaptor 245for connecting the prosthetic foot to a user's residual limb or toanother prosthetic component (e.g., pylon, socket). The prostheticrunning foot 241 can be a monolithic member made of a fiber material(e.g., carbon fiber). In other embodiments, the prosthetic running foot241 can be modular and/or made of other suitable materials. Theprosthetic running foot 241 shown is Össur Cheetah, however, it will beunderstood that the pump systems described herein can also be adaptedfor use with other prosthetic running feet and components.

The pump system 239 comprises a pump mechanism 247 having a suction cuptype configuration. The pump mechanism 247 includes an elastomermembrane 249 arranged to be positioned on and form seal with a sealingsurface 251 defined along a posterior aspect of the plate-like member243. The membrane 249 has a compliant configuration.

The pump mechanism 247 relies upon deformation of the membrane 249 tomove been an original configuration in which the volume of a fluidchamber 253 defined between the sealing surface 251 and a bottom of themembrane 249 is zero or near-zero, and an expanded configuration inwhich the volume of the fluid chamber 253 is increased. The membrane 249can have any suitable configuration.

The membrane 249 defines a passageway 255 in fluid communication withthe fluid chamber 253. In the illustrated embodiment, a fluid regulatoror valve assembly 257 can be associated with the passageway 255. Thevalve assembly 257 is arranged to only allow fluid to enter the fluidchamber 253 via the passageway 255. The valve assembly 257 can compriseany suitable valve assembly. A housing 261 or fitting can be associatedwith the passageway 255. The housing 261 can be arranged to attach thepump mechanism 247 to a tube in fluid communication with a socket. Thehousing 261 can connect the membrane 249 to a support member describedbelow.

As the pump mechanism 247 moves toward the original configuration,pressure within the fluid chamber 253 can increase until the sealbetween the membrane 249 and the sealing surface 251 is broken, allowingfluid in the fluid chamber 253 to escape or be expelled out under thesides of the membrane 249. The pump mechanism 247 thus does not requirean outlet valve assembly, reducing the overall weight and profile of thepump system 239.

A support member 259 is arranged to move the pump mechanism 247 betweenthe original and expanded configurations. The support member 259 canhave a rigid configuration. The support member 259 can have any suitableshape but is shown having a curvature generally corresponding to thecurvature of the plate-like member 243.

The support member 259 can be attached to a posterior side of theplate-like member 243. A proximal end portion 265 of the support member259 is attached to the proximal end of the plate-like member 243. Adistal end portion 267 of the support member 259 is attached to a centerportion of the membrane 249. The support member 259 can define anopening or slot for connecting the membrane 249 to the support member259.

During stance, the plate-like member 243 compresses and moves away fromthe distal end portion 267 of the support member 259, which, in turn,causes the support member 259 to pull the center portion of the membrane249 away from the sealing surface 251, increasing the volume of thefluid chamber 253. This increase in volume of the fluid chamber 253creates a vacuum in the pump mechanism 247, pulling fluid into the pumpmechanism.

In swing or when the load is removed from the foot 247, stored energy inthe plate-like member 243 expands the plate-like member 243 and moves ittoward the distal end portion 267 of the support member 259, bringingthe sealing surface 251 and the center portion of the membrane 249together. During the return of the sealing surface 251 toward the centerportion of the membrane 259, increased pressure in the fluid chamber 253can break the seal between the membrane 259 and the sealing surface 251,allowing fluid in the fluid chamber 253 to be expelled out under themembrane 249.

The pump system can thus generate a vacuum in a socket using compressionand expansion of a sport foot without undesirably affecting thefunctionality of the foot or significantly increasing the bulk of therunning foot.

In addition, because the membrane 249 is compliant, the membrane 249 cancreate and maintain the seal between the bottom of the membrane 249 andthe sealing surface 251 even as the sealing surface 251 moves andchanges shape with the expansion and compression of the plate-likemember 243. This advantageously allows the pump mechanism 247 to fit ona wider variety of surfaces, feet and prosthetic components.

According to a variation, the pump system 247 includes a closure-assistmechanism 271 arranged to bias the pump mechanism 247 toward theoriginal configuration. In an embodiment, the closure-assist mechanism271 can comprise a foam member 273 having a resilient configurationpositioned between the interior surface of the support member 259 andthe outer surface of the membrane 249.

As the pump mechanism 247 moves toward the expanded configuration, thefoam member 273 is compressed between the membrane 249 and the supportmember 259, storing energy in the foam member 273. When the force on themembrane 249 is removed or reduced, the stored energy or resilientproperties of the foam member 273 can force the center portion of themembrane 249 back toward the sealing surface 251, biasing the pumpmechanism 247 toward the original configuration. Optionally, the centerportion of the membrane 249 can be extend through an opening 277 definedin the foam member 263.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments are contemplated. For instance, the membraneused in the embodiments described can vary in thickness in differentareas and in shape. The membrane may be a cylindrical shape, a taperedshape, or any other suitable shape. In other embodiments, the pumpmechanism can include a plurality of closure-assist mechanisms such as amagnetic closure element and a resilient closure element.

In yet other embodiments, the pump mechanism can be attached to a pylon,prosthetic ankle, or any other suitable prosthetic component. In otherembodiments, embodiments of the pump system can include two, three, orany other suitable number of pump mechanisms. In embodiments where thepump system is associated with first and second parts rotatable about ajoint, it will be appreciated that the first part may rotate relative tothe second part, the second part may rotate relative to the first part,or both parts may rotate about the joint. Further, it will beappreciated that the pump system may be arranged to move the pumpmechanism into the expanded configuration in stance, swing, or in bothstance and swing.

In other embodiments, the pump mechanism can include one or morefeatures arranged so that a user can regulate or control the level ofvacuum generated by the pump mechanism. For instance, the pump mechanismcan include a plurality of membranes having different stiffness and/orthickness that can be selected by a user to increase or decrease thevolume change of the fluid chamber, which, in turn, controls the vacuumgenerated by the pump mechanism. In other embodiments, the pumpmechanism may include an adjustable closure-assist mechanism that can bemanipulated by a user to increase or decrease the level of forcerequired to move the pump mechanism between the expanded and originalconfigurations, which, in turn, controls the vacuum generated by thepump mechanism.

The various aspects and embodiments disclosed herein are for purposes ofillustration and are not intended to be limiting. Additionally, thewords “including,” “having,” and variants thereof (e.g., “includes” and“has”) as used herein, including the claims, shall be open ended andhave the same meaning as the word “comprising” and variants thereof(e.g., “comprise” and “comprises”).

The invention claimed is:
 1. A prosthetic system comprising: first andsecond parts rotatable relative to one another about a joint, the firstand second parts adapted to form at least part of a weight bearingconnection between a prosthetic foot and a socket, the first partdefining an upper section arranged to connect to the socket and thesecond part defining a lower section arranged to connect to a prostheticfoot, the second part being spaced apart from the first part by aclearance; and a pump system including: a pump mechanism operativelyconnected to the first and second parts such that relative rotationbetween the first and second parts about the joint moves the pumpmechanism between a predetermined configuration in which a volume of afluid chamber defined by the pump mechanism is zero or near-zero, and anexpanded configuration in which the volume of the fluid chamber isincreased, the pump mechanism including a housing, a membrane, and atleast one valve assembly arranged to control movement of fluid intoand/or from the pump mechanism; a movable member including a first endportion connected to the membrane and a second end portion connected tothe first part; wherein when the first and second parts are in thepredetermined configuration, the first and second parts are alignedalong a same axis defined by the weight bearing connection and extendingfrom the prosthetic foot to the socket.
 2. The prosthetic system ofclaim 1, wherein the membrane is connected at or near its center pointto the movable member and an outer radial edge portion of the membraneis connected to the housing.
 3. The prosthetic system of claim 1,wherein the membrane is connected to the movable member by a connector.4. The prosthetic system of claim 1, wherein the movable memberpivotally connects to the housing.
 5. The prosthetic system of claim 1,wherein deformation of the membrane increases the volume of the fluidchamber.
 6. The prosthetic system of claim 1, wherein the housing isattached to the second part and the first part is operably connected toa center portion of the membrane.